controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName:'Ember Twiddle'
});

router.js

import Ember from 'ember';
var Router = Ember.Router.extend({
  location: 'none'
});

Router.map(function() {
});

export default Router;

styles.app.css

body { margin: 12px 16px }

templates.application.hbs

<h1>Welcome to {{appName}}</h1><br><br>
<button class="btn btn-lg btn-info">Button</button>
{{outlet}}<br><br>

twiddle.json

{
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.9.1/jquery.js",
    "ember": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/1.13.5/ember.js",
    "ember-data": "https://cdnjs.cloudflare.com/ajax/libs/ember-data.js/1.13.5/ember-data.js",
    "bootstrap-css": "https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/3.3.5/css/bootstrap.css"
  }
}